Verbatim text: Heidel, B. L. and J. Handley. 2007. Penstemon laricifolius Hook. & Arn. Ssp. exilifolius (A. Nels.) D. D. Keck (Larchleaf Beardtongue): A Technical Conservation Assessment. Laramie.
Author: Heidel, B.L., Handley, J.
Year: 2007
Title: Penstemon laricifolius Hook. & Arn. Ssp. exilifolius (A. Nels.) D. D. Keck (Larchleaf Beardtongue): A Technical Conservation Assessment